Final answer:
Smoking during pregnancy is known to cause miscarriage and low birth weight in the developing embryo as it is a teratogen that reduces blood oxygen levels and exposes the baby to harmful chemicals.
Step-by-step explanation:
Smoking during pregnancy may cause miscarriage and low birth weight for the developing embryo. When a mother smokes, the developing baby experiences reduced blood oxygen levels and exposure to harmful chemicals found in cigarette smoke. According to health research, including the Centers for Disease Control and Prevention, smoking while pregnant can result in numerous adverse outcomes, such as premature birth, low-birth-weight infants, stillbirth, and sudden infant death syndrome (SIDS). Additionally, smoking can lead to growth reta_rdation, prelabor rupture of the membranes, preterm labor, and abruption of the placenta. Therefore, option d. Smoking is the correct answer as it is a known teratogen that can negatively affect the development of the embryo and result in the mentioned health issues.